Foam sheets, or pads, have long been used as whole body supports for bed patients, the pad being overlaid upon a bed mattress and thereafter covered with a textile sheet. These pads have been shown to be effective in aiding in the prevention of decubitus ulcers which appear to be the result of adverse combinations of heat, moisture, pressure and/or shear between a body member, such as a bony protuberance, and a supporting surface. The prior art foam pads provide a limited degree of aeration to the patient and commonly are formed with a plurality of conical peaks spaced apart from one another over the supporting surface of the pad, such peaks alternating with valleys therebetween. Albeit that such pads have been found useful, they suffer from well known deficiencies such as the tendency of the peaks to collapse and thereby cut off the desired aeration between the body member and the pad. Further, when these peaks collapse, the pad becomes little more than a flat surface so that there is developed a tendency toward shear forces between the body member and the pad, which combined with the lack of aeration, promotes decubitii.
Collapse of the peaks of the prior art pads is felt to be a function of their geometry, as well as the physical characteristics of the foam, i.e. its density, etc. Specifically, the peaks of the prior art must be of substantial respective heights in order for them to be effective as supports and maintain the body member away from the flat base of the pad if aeration is to occur. In foam pads of like densities, the higher peaks tend to collapse more readily and such collapse tends to be more complete, that is, the peaks tend to bend until they are in contact with the base as opposed to shorter peaks tending to compress and bend simultaneously so that the shorter peaks continue to provide a degree of separation of the body member from the base of the pad. Shorter peaks, however, are less comfortable to the patient and tend to develop substantial pressure points where the shear effect can come into play and promote decubitii.